Function Difference Adee43
1. **Problem Statement:** We are given the graphs of the derivatives $f'(x)$ and $g'(x)$ and asked to determine which graph could represent the function $h(x) = f(x) - g(x)$.
2. **Key Concept:** The derivative of $h(x)$ is given by
$$
h'(x) = f'(x) - g'(x).
$$
This means the graph of $h'(x)$ is the vertical difference between the graphs of $f'(x)$ and $g'(x)$ at each $x$.
3. **Given:**
- $f'(x)$ is a ray starting at the origin and pointing upwards and to the right, so $f'(x)$ is increasing and positive for $x>0$.
- $g'(x)$ is a ray along the positive $x$-axis, so $g'(x) = 0$ for all $x$.
4. **Calculate $h'(x)$:**
Since $g'(x) = 0$, we have
$$
h'(x) = f'(x) - 0 = f'(x).
$$
Therefore, $h'(x)$ has the same shape as $f'(x)$.
5. **Interpretation:**
- $h'(x)$ is increasing and positive for $x>0$.
- Integrating $h'(x)$ to get $h(x)$, since $h'(x)$ is increasing and positive, $h(x)$ will be a function that is increasing and concave up.
6. **Matching with options:**
- Option (a): Parabola opening upwards with vertex at origin — this matches an increasing, concave up function starting at zero.
- Option (b): Increasing linear function — derivative would be constant, but $h'(x)$ is increasing.
- Option (c): Parabola opening upwards but vertex not at origin — possible but less likely since $h'(0) = f'(0) - g'(0) = 0$ implies vertex at origin.
- Option (d): Horizontal line — derivative zero, contradicts $h'(x)$ increasing.
**Final answer:** The graph of $h(x)$ is best represented by option (a).
$$\boxed{\text{Option (a)}}$$